/Engine/Plugins/FX/Niagara/Source/NiagaraShader/Public/NiagaraShaderParticleID.h
void NiagaraFillGPUIntBuffer ( [FRHICommandList](API\Runtime\RHI\FRHICommandList) & RHICmdList, [ERHIFeatureLevel::Type](API\Runtime\RHI\ERHIFeatureLevel__Type) FeatureLevel, [FRHIUnorderedAccessView](API\Runtime\RHI\FRHIUnorderedAccessView) * BufferUAV, uint32 NumElements, int32 FillValue )